The historic observation of two black holes in orbit was achieved by astronomers for the first time. This remarkable event occurred within the quasar OJ287, located approximately 5 billion light-years away in the constellation Cancer. The findings were published on October 9 in The Astrophysical Journal, confirming long-held theories regarding black hole pairs.
Scientists have theorized for decades that some of the universe”s brightest objects, known as quasars, might harbor dual black holes engaged in a gravitational dance. The new research utilized data from an array of telescopes, both on Earth and in space, to achieve this groundbreaking observation.
In the OJ287 system, the two supermassive black holes are bound in a 12-year orbital cycle. Although black holes themselves are invisible, their influence can be detected through the high-speed particle jets they emit. One jet originates from a smaller black hole, while the second is associated with a massive black hole weighing 18 billion solar masses, roughly half the size of the largest black holes recorded.
The significant advancement in this research was made possible through the use of the Russian satellite RadioAstron, which operates at a distance reaching halfway to the Moon. The resulting images are nearly 100,000 times clearer than those produced by standard optical telescopes.
The quasar OJ287 has intrigued astronomers for over a century, with its brightness initially documented in the 19th century. However, the peculiar 12-year brightness fluctuation was first noted in 1982 by Finnish astronomer Aimo Sillanpää, hinting at the presence of two black holes.
Previous technology lacked the precision required to confirm this theory, although instruments like NASA”s TESS satellite recognized the pattern of light variations. A major breakthrough occurred when researchers from the University of Turku, led by Mauri Valtonen, employed sophisticated radio interferometry techniques on OJ287. Their findings aligned perfectly with theoretical models, allowing them to accurately locate both black holes.
Valtonen stated that while the black holes themselves are completely dark and undetectable, the surrounding glowing gas and particle jets provide crucial evidence of their existence. This development enables scientists to observe such cosmic phenomena in real time and supports the long-standing theory that black holes can exist in pairs.
Although gravitational wave evidence has hinted at the existence of black hole pairs, researchers at Turku are cautious about drawing definitive conclusions without further visual confirmation. Another high-resolution image is necessary to ensure that the observation represents two distinct black holes rather than overlapping jets from a single one.
Despite the need for additional verification, this discovery marks an exciting milestone. If validated, OJ287 could become the first confirmed example of two black holes in orbit, laying a foundation for understanding the formation and evolution of supermassive black holes throughout the universe.
